Rust
Outlook --Download Attachments for a Specific Message

Demonstrates how to download the attachments for a particular email message.
Note: This example requires Chilkat v9.5.0.67 or greater.
Chilkat Rust Downloads

Rust
let mut success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

let http = chilkat::Http::new();

// Use your previously obtained access token here:
// See the following examples for getting an access token:
//    Get Microsoft Graph OAuth2 Access Token (Azure AD v2.0 Endpoint).
//    Get Microsoft Graph OAuth2 Access Token (Azure AD Endpoint).
//    Refresh Access Token (Azure AD v2.0 Endpoint).
//    Refresh Access Token (Azure AD Endpoint).

http.set_auth_token("MICROSOFT_GRAPH_ACCESS_TOKEN");

let sb_response = chilkat::StringBuilder::new();

// Sends:  GET /users/{user_id | userPrincipalName}/messages/{message_id}/attachments
// Note: It is also possible to use the literal string "me" for the current logged-on user.
// For example: GET /me/messages/{message_id}/attachments

http.clear_url_vars();
let _ = http.set_url_var("userPrincipalName", "chilkatsoft@outlook.com");

// Assume we already have a message ID from previously listing the messages in a folder
let message_id = "AAMkADYzZWE3YmZmLWU0YzgtNGNkZC04MGE1LWFiYTFlNTRlY2QwYQBGAAAAAAAu7cUXL5YOTrdsUIw7-v8FBwBUcG0qWqkmQYqWLHQataQxAACnwqJUAABUcG0qWqkmQYqWLHQataQxAACnwrnOAAA=".to_string();
let _ = http.set_url_var("message_id", &message_id);

// Send the request to download the attachments.
success = http.quick_get_sb("https://graph.microsoft.com/v1.0/users/{$userPrincipalName}/messages/{$message_id}/attachments", &sb_response).is_ok();
if (!success) && (http.last_status() == 0) {
    println!("{}", http.last_error_text());
    return;
}

// The attachment data is contained within the JSON response.
let json = chilkat::JsonObject::new();
let _ = json.load_sb(&sb_response);
json.set_emit_compact(false);

println!("Status code = {}", http.last_status());
if http.last_status() != 200 {
    println!("{}", json.emit().unwrap_or_default());
    println!("Failed.");
}

// This is a sample JSON response.  The code for parsing and extracting/saving the attachments
// is shown below.

// 	{
// 	  "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('chilkatsoft%40outlook.com')/messages('AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAL8huv8AAADn68XtMop0TpsYJGpfKXY9AAAAwSju2wAAAA%3D%3D')/attachments",
// 	  "value": [
// 	    {
// 	      "@odata.type": "#microsoft.graph.fileAttachment",
// 	      "id": "AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAL8huv8AAADn68XtMop0TpsYJGpfKXY9AAAAwSju2wAAAAESABAAft6wtbaSJU6sgQLi98DI0Q==",
// 	      "lastModifiedDateTime": "2017-05-10T00:30:51Z",
// 	      "name": "fishing.pdf",
// 	      "contentType": "application/pdf",
// 	      "size": 295680,
// 	      "isInline": false,
// 	      "contentId": "F861B218BE380F44B16933097FDDACFC@namprd20.prod.outlook.com",
// 	      "contentLocation": null,
// 	      "contentBytes": "JVBERi0xLjMKJcfsj6 ... yZWYKMjk0MzY5CiUlRU9GCg=="
// 	    },
// 	    {
// 	      "@odata.type": "#microsoft.graph.fileAttachment",
// 	      "id": "AQMkADAwATM0MDAAMS1iNTcwLWI2NTEtMDACLTAwCgBGAAADsVyfxjDU406Ic4X7ill8xAcA5_vF7TKKdE6bGCRqXyl2PQAAAL8huv8AAADn68XtMop0TpsYJGpfKXY9AAAAwSju2wAAAAESABAAXS7qXQ-iRUCYXnhJpN8Ihg==",
// 	      "lastModifiedDateTime": "2017-05-10T00:30:51Z",
// 	      "name": "testCert.cer",
// 	      "contentType": "application/octet-stream",
// 	      "size": 1674,
// 	      "isInline": false,
// 	      "contentId": "5E51FA33EF0F8941ACC8260395CB1A33@namprd20.prod.outlook.com",
// 	      "contentLocation": null,
// 	      "contentBytes": "MIIFRjCCBC6gAwIBA ... 7pt3C5w=="
// 	    }
// 	  ]
// 	}

let sb_save_path = chilkat::StringBuilder::new();
let attach_data = chilkat::BinData::new();
let last_mod = chilkat::DateTime::new();
let fac = chilkat::FileAccess::new();

let mut i = 0;
let num_messages = json.size_of_array("value");
while i < num_messages {
    json.set_i(i);

    println!("name: {}", json.string_of("value[i].name").unwrap_or_default());
    println!("contentType: {}", json.string_of("value[i].contentType").unwrap_or_default());
    let size_in_bytes = json.int_of("value[i].size");
    println!("size: {}", size_in_bytes);

    // Extract the data and save to a file.
    let _ = sb_save_path.set_string("qa_output/");
    let _ = sb_save_path.append(&json.string_of("value[i].name").unwrap_or_default());

    let _ = attach_data.clear();
    let _ = attach_data.append_encoded(&json.string_of("value[i].contentBytes").unwrap_or_default(), "base64");
    let _ = attach_data.write_file(&sb_save_path.get_as_string().unwrap_or_default());

    // Get the last-modified date/time and set the output file's last-mod date/time..
    let _ = last_mod.set_from_timestamp(&json.string_of("value[i].lastModifiedDateTime").unwrap_or_default());
    let _ = fac.set_last_modified(&sb_save_path.get_as_string().unwrap_or_default(), &last_mod);

    println!("----");

    i = i + 1;
}

// The output of the above loop is:
// 
// 	name: fishing.pdf
// 	contentType: application/pdf
// 	size: 295680
// 	----
// 	name: testCert.cer
// 	contentType: application/octet-stream
// 	size: 1674
// 	----
//